The present invention relates generally to wheel trim retention systems (including assembly methods) and more particularly to retention systems particularly designed for use with polymeric composition trim members.
Polymeric compositions are particularly desirable for use in fabricating wheel trim because of their ability to be easily and quickly molded into almost any shape or design, they allow fabrication of relatively lightweight wheel trim and they are not subject to corrosion. However, because such materials may not perform well when subjected to continuous stress such as may be exerted thereon by many types of conventional retention systems, use of these materials has not been as widely accepted as might be expected given the various advantages of such materials for this application.
A number of retention systems have been designed for use with polymeric composition wheel trim which utilize either a retention band or separate retention clips having a number of projections thereon which bitingly engage a portion of the trim member such as the inner or outer surfaces of a flange portion. However, the use of a biting engagement results in a localized stress being exerted on the trim member. This stress may result in cracking or otherwise damaging the wheel trim over a period of time or when the wheel trim is subjected to low temperature extremes.
While numerous attempts have been made to design a retention system particularly suited for use with polymeric composition wheel trim providing retention means in the form of an annular band or separate clips which do not subject the trim material to high localized stresses, most of these systems require either assembly of a number of separate components or performing additional assembly operations thereon to secure the retention means to the trim member. For example, in one form the retention means is secured to the wheel trim by rolling or otherwise forming a metal strip, which may be either a separate piece or an integral part of a retention band, over the outer peripheral edge of the trim ring. In another form, a number of pins are provided on the trim member which are received within openings in the retention band and then heat staked or otherwise deformed so as to provide an enlarged head thereon. While some of these systems may offer satisfactory performance, the need to fabricate and assemble numerous parts or perform additional operations on the wheel trim results in increased manufacturing costs.
The present invention provides a wheel trim having a retention system which overcomes these disadvantages by eliminating the need to perform additional assembly or manufacturing operations in connection with the attachment of the retention system to the wheel trim and yet also provides a retention system which substantially reduces the stresses to which the wheel trim may be subjected to. Additionally, the retention system of the present invention is designed to be assembled and secured to the trim ring as a single unit thereby assisting in reducing manufacturing costs associated therewith.
The retention system of the present invention includes a wheel trim which may be fabricated from a polymeric composition and which includes means defining a generally axially inwardly extending radially outwardly facing flange portion. An annular retention band is also provided which is designed so as to enable it to be easily and economically manufactured in strip form and which is designed to cooperate and form a mechanical interlock with the flange portion of the trim member so as to retain the retention band and trim member in assembled relationship. Because of the nature of the mechanical interlock, the retention band does not need to tightly engage the flange portion and thus the problems associated with subjecting polymeric materials to continuous stress are substantially eliminated. Additionally, because the retention band is of a design which enables it to be easily and conveniently manufactured in strip form such as by rolling or the like and because it may be directly attached to the trim member without the need to manufacture and separately attach additional screws or other means to secure the retention band to the trim member, the present retention system is very economical in terms of both labor and time to manufacture. Thus, the present invention provides a secure reliable retention system which allows the advantages offered through use of polymeric composition trim members to be obtained both economically and efficiently.
Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.